Electrophysiology catheters are commonly-used for mapping electrical activity in the heart. Various electrode designs are known for different purposes. In particular, catheters having basket-shaped electrode arrays are known and described, for example, in U.S. Pat. Nos. 5,772,590, 6,748,255 and 6,973,340, the entire disclosures of each of which are incorporated herein by reference.
Basket catheters typically have an elongated catheter body and a basket-shaped electrode assembly mounted at the distal end of the catheter body. The basket assembly has proximal and distal ends and comprises a plurality of spines connected at their proximal and distal ends. Each spine comprises at least one electrode. The basket assembly has an expanded arrangement wherein the spines bow radially outwardly and a collapsed arrangement wherein the spines are arranged generally along the longitudinal axis of the catheter body.
It has been observed that there is an increased risk of thrombus formation when using catheters that change shape from a linear delivery configuration to an expanded diagnostic configuration. Thrombus formation may occur around device features that slow down the flow of blood. Catheters typically release irrigation fluid to reduce this risk. However, diagnostic catheters include only a single irrigation lumen that has a port at the distal end of the catheter. Oftentimes, this single port is not sufficient to flush the entire device from the proximal end to the distal end which may lead to thrombus formation. Therefore, it is desirable to design a catheter that has an improved irrigation system to reduce or eliminate the risk of thrombus formation. The techniques of this disclosure satisfy this and other needs as described in the following materials.